One of the important underlying assumptions of all item response theory (IRT) models is that of local independence. This assumption requires that the response to an item on a test not be influenced by the response to any other items. This assumption is often taken for granted, with little or no scrutiny of the response process required to answer…

The purpose of this study was to determine the validity of the American College Test (ACT) in predicting academic achievement of students from an area which is culturally, economically, and educationally depressed. The population, chosen from 6 community colleges serving the Appalachian region of Kentucky, consisted of 1,127 full time (12 or more…